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bioRxiv · 10.1101/2024.02.05.578907

OsNF-YB7 inactivates OsGLK1 to inhibit chlorophyll biosynthesis in rice embryo

Yang, Z.·Bai, T.·E, Z.·Niu, B.·Chen, C.
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Abstract

As a master regulator of seed development, Leafy Cotyledon 1 (LEC1) promotes chlorophyll (Chl) biosynthesis in Arabidopsis, but the mechanism underlying this remains poorly understood. Here, we found that loss of function of OsNF-YB7, a LEC1 homolog of rice, leads to chlorophyllous embryo, indicating that OsNF-YB7 plays an opposite role in Chl biosynthesis in rice compared with that in Arabidopsis. OsNF-YB7 regulates the expression of a group of genes responsible for Chl biosynthesis and photosynthesis by directly binding to their promoters. In addition, OsNF-YB7 interacts with Golden 2-Like 1 (OsGLK1) to inhibit the transactivation activity of OsGLK1, a key regulator of Chl biosynthesis. Moreover, OsNF-YB7 can directly repress OsGLK1 expression by recognizing its promoter in vivo, indicating the involvement of OsNF-YB7 in multiple regulatory layers of Chl biosynthesis in rice embryo. We propose that OsNF-YB7 functions as a transcriptional repressor to regulate Chl biosynthesis in rice embryo.

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Yang, Z., Bai, T., E, Z., Niu, B., Chen, C.. 2024-02-05. OsNF-YB7 inactivates OsGLK1 to inhibit chlorophyll biosynthesis in rice embryo. https://doi.org/10.1101/2024.02.05.578907

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